; Vyskot and Hobza, 2004 ). Exogenous application of plant growth regulators can modify or reverse sex morphology in plants ( Galoch, 1978 ). In hemp, auxins, ethylene, and cytokinins promote the formation of female flowers on male plants; gibberellins
, this study investigated flower bud differentiation, mega-micro spore production, and male-female gametophyte development in this species. The results of this study might provide practical guidance and a theoretical basis for the high-yield cultivation
differentiation of lateral inflorescences ( Chen, 1990 , 1994 ; Davenport, 2000 ), resulting in a decrease in the total number of flowers and female flowers, subsequently reducing fruit yield. Few studies have been carefully employed on the relationship between
When pumpkins are grown in elevated temperatures (32/27 °C day/night) for 1 week during flower development, fewer female flower buds are formed than at normal temperatures (20/15 °C) and only a small percentage of these reach anthesis. To determine if application of the ethylene-releasing compound ethephon can overcome the suppression of female flowers at high temperatures, `Baby Bear' pumpkin plants were sprayed at the two-leaf stage with 100 or 300 μL L–1 ethephon and then grown in hot and cool greenhouse compartments. At 20/15 °C, 17% of the first 15 main stem nodes produced female flower buds on control plants and virtually all of these developed into open flowers. The higher rate of ethephon increased female bud percentage to 37%. At 32/27 °C, only 3% of the nodes formed female flower buds and 2% flowered. Application of ethephon did not significantly increase female expression at high temperature, and none of the buds reached anthesis. Treatment with the inhibitor of ethylene action silver thiosulfate reduced female flower bud formation at the low temperature and entirely suppressed female flower buds at high temperature. In two additional experiments, these treatments were applied to two cultivars grown at a less extreme 32/20 and at 20/15 °C. Female buds and open flowers were moderately increased by ethephon in the high temperatures, suggesting that ethephon might foster female flowering in less extreme temperatures. Further work is needed to determine if ethephon treatment can overcome the heat-induced inhibition of female flowers in pumpkin under field conditions.
., 2020 ; Yu et al., 2017 ). Among angiosperms, 89%∼90% of species are hermaphroditic with their flowers possessing both stamens and pistils, 6%∼7% are dioecious with only female or male flowers on a single plant, and 5% are monoecious bearing separate
Abstract
Ethephon applied as a foliar spray caused an androecious (all-male) line of Cucumis sativus L. to produce pistillate flowers analogous to those of monoecious phenotypes. The degree of conversion depended on the concentration of ethephon and stage of growth at the time of application. In the greenhouse, a concentration of 50 ppm applied at the 3- or 4-leaf stage was the best treatment for induction of pistillate flowers without marked inhibition of growth.
Hand pollinated pistilate date palm flowers were removed 2, 6, 10, 16, 20 hours after pollination, fixed. cleared with 8N NaOH and stained with aniline blue. The Fluoresced pollen tubes were abserved under ultra violet microscope. It was noted that under natural conditions with mean temperature of 19C pollen tube reached the ovary after 16 hours.
Viability test of fresh and stored pollen grains using Brewbaker & Kwack's media at room temperature was 85 and 52.5%. respectively.
production because female inflorescences accumulate significantly greater cannabinoid content than male inflorescences ( Small, 2015 ). Monoecious plants, which have both male and female flowers, occur occasionally in hemp, and cultivars have been selected
some are shrubs; leaves are alternate, pinnate, and leathery; female and male flowers are on separate trees (i.e., they are dioecious); pistillate flowers are borne in loose axillary panicles and staminate flowers are axillary and more compact; and the
, with staminate vines being more common than female vines ( Reimer and Detjen, 1910 ), although a few naturally occurring hermaphroditic vines have been described ( Detjen, 1917 ). The perfect hermaphroditic muscadine flower consists of a normal pistil